Drag the bowl, or use the arrow keys. Catch food. A caught mouse costs a life.
CHONK with a heart flies by on even levels. Catch it for one life, or +25 if you already have three.
A castle gives +80 and a short shield. A shield blocks one mouse. Every third level unlocks new food. The last 6 seconds of a level are harder. The bowl returns to the bottom after each level.
After level 45 the game continues and stays hard.